adb - Forgot Oneplus One pin. How to enable usb debugging?

I forgot my oneplus one pin. I have tried using google device manager and have tried putting in my pin (150+ times) to be prompted for my google account.

I was thinking if it would be possible for me to enable usb debugging and use adb to unlock my oneplus one

I was trying to do what the third answer in this thread suggests How to enable USB Debugging in Android if forgotten pattern for screen-unlock?

but am unable to follow, specifically, i don't know what to do when it says to mount "Data".

thanks in advance.